Carbon 13 H. pylori test refers to the Carbon 13 Urea Breath Test, which is generally less than 4 DOB is considered normal. Carbon 13 refers to the carbon 13 urea breath test, which requires the patient to breathe out on an empty stomach and then the patient swallows a capsule containing carbon 13 labeled urea. Since H. pylori has urease activity, it can break down the carbon 13-labeled urea into carbon dioxide and water containing carbon 13 labeling. After 30 minutes of sitting still, have the patient exhale again and compare the change in carbon 13-labeled carbon dioxide values between the two exhales before and after. If the increase in value is greater than 4 DOB, it suggests that the patient is infected with H. pylori. In the event of H. pylori infection, it is recommended to seek prompt medical attention, follow the doctor’s instructions for further examination, clarify the cause with the help of the doctor, and carry out targeted treatment or therapy.